Automatic tracker attachment.



J. S. MAXWELL.

AUTOMATIC TRACKER ATTACHMENT.

APPLICATION FILED .OCT. [6 I913. 1,21 5,297. Patented Feb. 6,1917.

3 SHEETS-SHEET witnesses attorneys r mum urns m, Illnvundm. WAINIKGIDNT p. c.

I. S. MAXWELL. AUTOMATIC TRACKER ATTACHMENT.

APPLICATION FILED OCT-16,19l3.

Patented Feb. 6, I917.

3 SHEETSSHEET 2.

m w 1r W. s M 0 4M witnesses nouns runs c l. S. MAXWELL.

AUTOMATIC TRACKER ATTACHMENT.

1 2 7 APPLICATION FILED OCT-16.1913. P m ted F b 6 1917 a n e a q 9 9 a snTssMET 3 witnesses 40 A;

, e/ z v UNITED sTAfr s PATENT oEEioE.

JOHN S. MAXWELL, OF RICHMOND, INDIANA, ASSIGNOR TO THE STARR PIANO COMPANY, OF RICHMOND, INDIANA, A CORPORATION OF INDIANA.

AUTOMATIC TRACKER ATTACHMENT.

Specification of Letters Patent.

Patented Feb. 6, 1917.

Application filed October 16, 1913. Serial No. 795,588.

To all whom it may concern:

Be it known that 1, JOHN S. MAXWELL, a citizen of the United States, residing at Richmond, in the county of Vayne and State of Indiana, have invented certain new and useful Improvements in Automatic Tracker Attachments; and I do hereby declare the following to be a full, clear, and exact description of the invention such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to player pianos and has for an object to provide a mechanism for automatically restoring the alinement between the traveling music sheet and the fixed tracker bar.

This is accomplished by mounting the feed spool in movable trunnions, one of which is pressed constantly inward by a spring while the corresponding outer movement of the other trunnion. is resisted by a cam, and the cam is moved in one direction or the other by a double pneumatic whose action is controlled by the position of the sheet itself at a point where it crosses the tracker bar, whereby a slight deflection of the sheet from its proper alinement will open specially formed valves.

The nature of the invention is such that these valves can be applied to most any type of tracker bar now on the market by forming recesses in the rear side of and openings through the tracker bar beyond its row of ports and in no way communicating therewith. The valves consist of boxes secured within said recesses and having spring tongues which project through the openings, and the remainder of the regulating mechanism can be placed at any suitable point within the player piano by a skilled machinist. Details of the invention are hereinafter more fully described and claimed.

In the drawings:

Figure 1 is a. view of the music box and associated parts with the sheet adjusting mechanism.

Fig. 2 is a top plan view of the adjusting mechanism, the top of the music box being removed on line 22 of Fig. 1.

Fig. 3 is a perspective view of the movable parts of the adjusting mechanism.

Fig. 4; is a view of the double pneumatic in side elevation showing the means of connecting the opposite movable walls.

Fig. 5 is a perspective view of the cam.

Fig. 6 is a view of one of the valves and valve blocks in side elevation.

Fig. 7 is a sectional view of one of the valve blocks.

Like characters of reference designate corresponding parts throughout the several views.

The improved adjusting mechanism which forms the subject matter of this application comprises a music box of substantially the usual and ordinary type wherein the cheek plates 10 serve to position a trunnion 11 slidable in the sleeve 12 and forced constantly toward the opposite wall of the music box by the spring 13. At the opposite side of the music box a trunnion 14: is also journaled in one of the cheek plates and is longitudinally slidable therein. The last mentioned trunnion is the driving trunnion,i a sprocket 15 being carried upon such trunnion driven by a sprocket chain 16 from the sprocket 17 which in turn is driven from the motor not shown. It will be apparent, therefore, that with a spool between thel trunnions 11 and 14 the tendency of the spring 13 is to force the spool continually to the right of the music box as shown in Fig.

1. To resist such constant tendency a cam lS'is mounted upon an arm 19 and the whole! 86 carried upon a rod 20 with the cam positioned so that the trunnion 14 abuts against such cam.

The shape of the cam as shown more particularly at Fig. 1 is such that as the rod 9.0 is turned in one direction the cam 18 permits the trunnion 14: to move farther away from the trunnion 11, and as the rod is turned in the other direction the trunnion 14 is moved toward the trunnion 11. i

To move such rod 20 and cam 18 there is mounted near the music box a double pneumatic 21 having movable walls 22 and 23 connected by a link 24 so that they move in unison. The rod 20 is connected with such jointed movable walls by means of a link 25 engaging an ear 26 of the pneumatic at one end and a crank arm 27 at the other end, such crank arm being rigidly and adj ustably connected with the rod 20. It will be apparent, therefore, that as the walls 22 and 23 of the pneumatic are moved the rod 20 will be rocked to move the cam 18 and thereby move the trunnion 14 longitudinally.

To produce such movement of the double 11$ pneumatic it is connected through the medium of a tube 28 with any usual exhaust chamber as employed ordinarily in such player pianos so that the pneumatic as a whole is subject to such exhaust. From one side of the pneumatic a tube 29 leads to one end of the tracker bar while a tube 30 leads from the opposite side of the pneumatic to the tracker bar.

At each end of the tracker bar and entirely beyond its row of ports a recess 41 is cut into it from its rear side as indicated in dotted lines in Fig. 2, and this recess is continued into a reduced opening ll which is carried through the face of the tracker bar as seen in Fig. 1, the opening being disposed in alinement with the head of the spool beneath. Into said recesses from the rear are set valve-blocks 32 and 33, held removably therein by screws 33, and at the rear ends of these blocks are projecting nipples 3 1 and 35 to receive the tubes 29 and 30 respectively. Each block is bored with an L-shaped passage 36 as seen in Fig. 7, its rear end communicating with the nipple and its front end opening out the side of the block toward the end of the tracker bar. Pivoted to the outer face of the block is a lever 38 carrying a valve 37 which closes the front end of the passage 36, and is held normally against the side of the block by a spring 39 coiled around the pivot of the lever. The latter has at its free forward end a tongue .40 which projects beyond the front end of the block and extends through the opening 41 in the tracker barprojecting slightly beyond the face of the latter as seen in Fig. 2. By this construction no part of the valve or valve mechanism is visible except the comparatively obscure tips of the tongues 40 which extend through the openings 4:1 in such tracker bar face. It will be, of course, apparent that the tongues are spaced properly to permit a music sheet to travel therebetween without touching either of them when it is in normal position and in proper alinement with the ports of the tracker bar. When, however, for any reason the sheet is diverted from its normal course either edge will contact with one of the tongues, thereby moving its lever 38 and valve 37 and opening the port to admit air to one block 32, whence it flows into one side or the other of the pneumatic 21 which will immediately respond by rotating the rod 20 and moving the cam 18 in engagement with the extrem ity of the trunnion 1a.

It will be seen that the cam 18 forms a positive stop for the trunnion 1 1 and the pneumatic 21 being balanced the device will not move in either direction except under the impetus of air admitted to the pneumatic and while the spring 13 tends to constantly move the spool in one direction the cam 18 as constantly resists such movement and permits such movement only when the cam 18 moves in one or the other of its directions of movement.

I claim:

In a piano player including a fixed tracker bar, feed spool, and longitudinally movable trunnions, an attachment comprising a double pneumatic, mechanism actuated thereby for adjusting the feed spool with relation to the tracker bar, the latter having recesses formed in its rear side and-continued into reduced openings extending through its face beyond its row of ports, a valve-block seated in each recess and having an L-shaped passage, connections between the rear end of said passage and the double pneumatic, a lever pivoted at its rear end to the outer side of the block and having a tongue at its front end projecting through the opening in the tracker bar, a valve on the lever closing the front end of the passage, a coiled spring around the pivot of the lever holding the .valve normally closed, and a screw in the tracker bar against the block, for the purpose set forth.

In testimony whereof I a'flix my signature in presence of two witnesses.

JOHN S. MAXWELL. Witnesses:

ARNOLD'E. PFEIFFER, WVALTER Boron.

Goples of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C. 

